1. Field of the Invention
The present invention relates to electrical connectors and, particularly, to an electrical connector capable of preventing tilted plugging.
2. Description of the Related Art
Most of multiple pole connectors having a large number of terminals have a plugging section with an elongated rectangular plugging face. For example, they have a rectangular plugging cavity for receiving a mating connector that has a rectangular plugging projection.
An example of such electrical connectors is disclosed by Japanese patent application No. 10-199626. This connector comprises a housing with an arranging plate having a face on which the contact sections of a plurality of terminals are arranged and a shield case spaced from the arranging plate so as to define a plugging cavity for receiving the plugging projection of a mating connector. A plurality of slots are provided in the plugging projection for supporting the contact sections of terminals.
Upon plugging, the arranging plate enters the slots, bringing the contact sections of terminals of both the connectors into contact with each other for electrical connection. This connector has no problem where both the connectors are plugged in the regular direction.
However, when the front edges of the plugging cavity and projection are at an angle upon plugging, part of the plugging projection abuts on the front end of the arranging plate within the plugging cavity, damaging the arranging plate. The arranging plate is made of the same material as the housing and is so thin that it is damaged by repeated strong impacts.
A key and a key slot are provided to prevent upside down plugging. However, the key and key slot are provided in the middle of the connectors so that they are not helpful for preventing the damage caused by such tilted plugging as described above.
Accordingly, it is an object of the invention to provide an electrical connector capable of preventing the tilted plugging, thus providing a protection upon handling the connector.
According to one aspect of the invention there is provided an electrical connector which comprises a substantially rectangular plugging projection to be plugged into a plugging cavity of a mating connector; a pair of projections or ridges provided on at least one of major faces of said plugging projection near opposite side edges of said major face so as to enter corresponding grooves of said mating connector in a regular plugging direction.
In the tilted plugging, a corner of the plugging projection tries to enter the plugging cavity of a mating connector. However, the projection provided on the front edge prevent such entrance. In the regular plugging direction, however, the projections enter the corresponding grooves of the mating connector to complete the plugging. The projections may be ridges to stabilize the guidance by the grooves.
The projections are provided on both major faces of said plugging projection and said projections on one of said major faces have a width and a distance therebetween that are different from those of said faces on the other major face to prevent not only tilted plugging but also upside down plugging.
According to another aspect of the invention there is provided an electrical connector comprising a plugging cavity defined by a rectangular tubular wall; a pair of grooves extending in a plugging direction in at least one of major faces of said tubular wall near opposite side edges so as to receive a corresponding projections of a mating connector in a regular plugging direction.
The grooves guide the projections of the other connector in the regular plugging direction. The grooves are provided in either the tubular wall of the housing or a shield case over the housing. The grooves may be recess that open toward only inside or slits that open through the tubular wall. In the case of the shield case, the grooves are slits that open through the sheet metal.
It is preferred that said shield case has tapered front edges that terminate front ends of said slits, making a continuous front circumference to maintain the strength of the shield case.